.. -*- rst -*-

   Copyright (c) 2022-2023 Nanook Consulting.  All rights reserved.
   Copyright (c) 2023 Jeffrey M. Squyres.  All rights reserved.

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.. The following line is included so that Sphinx won't complain
   about this file not being directly included in some toctree

Export an environment variable, optionally specifying a value. For
example:

* ``-x foo`` exports the environment variable ``foo`` and takes its
  value from the current environment.
* ``-x foo=bar`` exports the environment variable name ``foo`` and
  sets its value to ``bar`` in the started processes.
* ``-x foo*`` exports all current environmental variables starting
  with ``foo``.